DNA has been obtained from approximately 20 major malformations for current and future investigations. We have recently expanded our investigations to include searching for copy number variants in rare defects. New York has an exceptionally valuable research resource in having approximately 250,000 births per year from which to identify children with rare defects. In addition to classic candidate gene approaches, cases have been selected for copy number variant studies. The laboratory work has now been completed on many of the conditions selected for copy number variant testing. Copy number variants have been identified in several conditions of interest. We have now published findings on heterotaxy and on posterior urethral valves demonstrating copy number variants of potential importance in both conditions and providing leads for future research. A report on Klippel Trenaunay Syndrome is currently in press. We have a new collaboration with the CDC's National Birth Defects Prevention Study. In conjunction with Dr. Paul Romitti at the University of Iowa, we will be searching for genetic factors associated with choanal atresia, a defect in which the nasal passages fail to develop normally. This study involves testing samples from New York State and from the collaborative group that formed the National Birth Defects Prevention Study. Laboratory analysis is being completed. We will be collaborating with another consortium following up on our work on craniosynostosis (see Justice et al. Nature Genetics). The previous work focused on saggital craniosynostosis. The future work will expand on this to look for genetic factors associated with defects in other sutures. This work has received external funding and is ongoing. We have established a collaboration with the Statens Serum Institut in Copenhagen, Denmark to examine genetic factors in congenital hydrocephalus. We have identified samples for confirmatory testing of SNPs from their GWAS study. Laboratory analysis is almost complete.